How long until someone else noticed?

I deliberately didn’t tell anyone I was using minox to grow my beard. I wanted to see when someone would notice and now 2 months in, the only one who noticed was my wife, and unfortunately not the beard gains but the minoxidil turning her white pillow cases yellowish/brownish. I can see some tiny belly’s hairs myself, but I’m curious how long it will take to be obvious for others.